sr.flsr.bevholt <- function (ssb, a, b) {
  r <- (ssb * a) / (ssb + b)
  return(r)  
}

sr.eqsim.bevholt <- function (ssb, a, b) {
  r <- ((ssb*a)/(1 + ssb*b))
  return(r)
}

sr.segreg <- function(ssb, a, b) {
  if (ssb > b)
    return (a*b)
  
  return (a*ssb)
}

# test values
a <- 754.26
b <- 1.0042e+8
ssb <- 89255193


rec <- sr.segreg(ssb, a, b)
print(rec/1e+9)

# segreg: 170t.t -> 75.7 m.rec
# bevholt: 170t.t -> 84.1 m.rec
# bevholt: 89t.t -> 59.5 m.rec
# segreg: 89t.t -> 67.3